JP5588809B2 - Inspection apparatus and inspection method - Google Patents

Description

  The present invention relates to an inspection apparatus and an inspection method.

  Conventionally, for example, as shown in Patent Document 1 below, a light source that emits light, a half mirror that reflects the light from the light source and irradiates the surface to be inspected, and an object sandwiching the half mirror An imaging unit that is arranged on the opposite side of the object and that images a surface to be inspected of the object irradiated with light from the light source via a half mirror, and a process for inspecting the object based on imaging data from the imaging unit There is known an inspection apparatus including a unit.

JP 2003-65963 A

  However, in the conventional inspection apparatus, in order to inspect the inspection target surface of the target object over a predetermined range, it is necessary to move the irradiation position of the light beam toward the inspection target surface of the target object. There was a risk of becoming.

  The present invention has been made in view of such circumstances, and provides an inspection apparatus and an inspection method capable of inspecting a surface to be inspected over a predetermined range while suppressing an increase in the size of the apparatus. The purpose is to do.

In order to solve the above problems and achieve such an object, an inspection apparatus according to the present invention includes a light source that emits a light beam, and a half that reflects the light beam from the light source and irradiates the surface to be inspected. An imaging means for imaging a surface to be inspected of a target object that is disposed on the opposite side of the target object sandwiching the half mirror and irradiated with light from the light source via the half mirror; and imaging from the imaging means A processing unit that inspects an object based on data, wherein the light source emits an annular light beam that gradually increases in diameter as the distance from the light source increases along the optical axis direction, Drive means for supporting the light source so as to be able to contact and separate along the optical axis direction with respect to the half mirror, the light source is moved in the optical axis direction by the drive means, and the diameter of the light beam on the surface to be inspected By varying the inspected While moving the irradiation position of the light beam at, it characterized that you inspect the surface to be inspected.

According to this invention, since the light source emits an annular light beam that gradually increases in diameter as it moves away from the light source along the optical axis direction, when the light source is moved along the optical axis direction by the driving means, The diameter of the annular light beam incident on the mirror will fluctuate. Therefore, by moving the light source along the optical axis direction by the driving unit, the diameter of the light beam is changed on the surface to be inspected of the object, and the irradiation position of the light beam on the surface to be inspected of the object can be moved. it can.
Thus, if the driving means for supporting the light source so as to be movable only in the optical axis direction is provided, the irradiation position of the light beam on the surface to be inspected of the object can be moved, and the apparatus becomes large. The surface to be inspected of the object can be inspected over a predetermined range while suppressing the above.
In the processing unit, for example, the difference between the annular shape of the light beam irradiated on the inspection surface of the object and the reference annular shape preset for each position on the inspection surface of the object is calculated. The portion of the imaging data obtained by long-time exposure of the imaging means while detecting or moving the light source in the direction of the optical axis has a density difference larger than a preset standard density difference, and its The presence or absence of a flaw can be inspected by detecting the size or the like.
Here, on the radiation surface of the light source that emits light, a circular light-shielding mask may be disposed in the entire area except the outer peripheral edge.

  The inspection method of the present invention is an inspection method for inspecting an object based on imaging data of a surface to be inspected of the object irradiated with light, and the object is detected using the inspection apparatus of the present invention. The surface to be inspected of the object is a peripheral surface that extends around the optical axis of the light beam that is reflected by the half mirror and travels toward the object.

According to this invention, since the inspection apparatus of the present invention is used, even if a scratch on the surface to be inspected of the object extends, for example, in a direction perpendicular to the circumferential direction, the processing section It is possible to reliably capture an image by the imaging unit to such an extent that it can be sufficiently detected.
That is, for example, in place of the half mirror and the light source in the inspection apparatus of the present invention, when a light source that uniformly irradiates light from the outside in the radial direction is disposed on the surface to be inspected, Reflected light that is reflected on the wound and directed toward the image pickup means is easily specularly reflected, and in the imaging data obtained by the image pickup means, the above-described scratched part and other parts of the surface to be inspected of the object, It is difficult to produce a difference in shading between the two, which may make it difficult to ensure inspection accuracy.
Here, the processing unit inspects the presence or absence of scratches on the surface to be inspected based on imaging data from the imaging unit, and the line width of the light beam is set to be equal to or less than the size of the scratches that need to be detected, The object may be a conical body, and an outer peripheral surface thereof may be the surface to be inspected.

  According to the inspection apparatus and the inspection method according to the present invention, it is possible to inspect the surface to be inspected over a predetermined range while suppressing the apparatus from becoming large.

It is the schematic of the inspection apparatus shown as one Embodiment which concerns on this invention.

Hereinafter, an embodiment of an inspection apparatus according to the present invention will be described with reference to FIG.
As shown in FIG. 1, the inspection apparatus 1 of the present embodiment includes a light source 11 that emits a light beam L, a half mirror 12 that reflects the light beam L from the light source 11 and irradiates the surface to be inspected of the object W. The imaging means 13 is arranged on the opposite side of the object W with the half mirror 12 interposed therebetween, and images the surface to be inspected of the object W irradiated with the light beam L from the light source 11 through the half mirror 12. And a processing unit 14 that inspects the object W based on the imaging data from.

In the present embodiment, the light source 11 faces the half mirror 12 in the horizontal direction, and the half mirror 12 reflects the light beam L from the light source 11 downward in the vertical direction. The object W is disposed directly below the half mirror 12.
Here, in this embodiment, the surface to be inspected of the object W is a peripheral surface that extends around the optical axis of the light beam L that is reflected by the half mirror 12 and travels toward the object W. In the illustrated example, the object W is a conical body, and the entire outer peripheral surface thereof is a surface to be inspected. Further, the object W is arranged coaxially with the optical axis of the light beam L that is reflected by the half mirror 12 and travels toward the object W.

The light source 11 is configured to emit an annular light beam L that gradually increases in diameter as the distance from the light source 11 increases along the optical axis direction. In addition, such an annular light beam L is obtained by, for example, arranging a circular light-shielding mask on the entire emission surface of the light source 11 that emits the light beam L except for the outer peripheral edge. Can radiate. Furthermore, the line width of the light beam L forming an annular shape is equal to or smaller than the size of a scratch that needs to be detected in the detection region.
The imaging means 13 is arranged coaxially with the object W, and can image the object W over the entire area from directly above. Further, the imaging data obtained by the imaging means 13 is a bright field image.

In the present embodiment, driving means 15 that supports the light source 11 so as to be able to contact and separate from the half mirror 12 along the optical axis direction is provided.
As the driving means 15, for example, a screwed structure including a screw shaft rotatably supported by a motor and a nut screwed to the screw shaft, or a piston is axially moved in a cylinder by fluid pressure. Examples include a cylinder / piston structure that is driven back and forth.

In the processing unit 14, a reference set in advance for each of the annular shape of the light beam L irradiated on the surface to be inspected of the object W and the position of the object W on the surface to be inspected obtained by the imaging unit 13. A preset reference light / dark difference in imaging data obtained by exposing the imaging means 13 for a long time while detecting a difference from the annular shape or moving the light source 11 in the optical axis direction. The presence or absence of a flaw is inspected by detecting a portion having a larger light and shade difference and its width.
In the former case, the light source 11 is moved intermittently in the direction of the optical axis, and the annular shape of the light beam L irradiated to the surface to be inspected of the object W is imaged by the imaging means 13 for each stop position. By detecting a difference between the formed annular shape and the above-described reference annular shape by the processing unit 14, the presence or absence of a flaw is inspected.

  In the inspection, the direction in which the light source 11 is moved in the optical axis direction by the driving means 15 can be gradually moved away from the half mirror 12 so that the irradiation position of the object W with respect to the surface to be inspected is gradually moved from the upper side to the lower side. Alternatively, by gradually approaching the half mirror 12, the irradiation position on the object W may be gradually moved upward from below.

As described above, according to the inspection apparatus 1 according to the present embodiment, the light source 11 emits the annular light beam L whose diameter gradually increases as the distance from the light source 11 increases along the optical axis direction. Is moved along the optical axis direction by the driving means 15, the diameter of the annular light beam L incident on the half mirror 12 changes. Accordingly, by moving the light source 11 along the optical axis direction by the driving unit 15, the diameter of the light beam L is varied on the surface to be inspected of the object W, and the light L is irradiated on the surface to be inspected of the object L. The position can be moved.
Thus, if the driving means 15 that supports the light source 11 so as to be movable only in the optical axis direction is provided, the irradiation position of the light beam L on the surface to be inspected of the object W can be moved, and the apparatus The surface to be inspected of the object W can be inspected over a predetermined range while suppressing the increase in size.

  Furthermore, since the above-described annular light beam L is irradiated onto the object W from directly above and the imaging means 13 images the object W from directly above, the scratches on the surface to be inspected of the object W are For example, even if it extends in a direction orthogonal to the circumferential direction, it becomes easy to image the deformation along the scratch of the light beam L irradiated to the surface to be inspected of the object W by the imaging means 13, and this scratch is The imaging unit 13 can reliably capture an image to the extent that the processing unit 14 can sufficiently detect it.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the said embodiment, although the conical body was shown as the target object W, it may replace with this, for example, may be a spherical body or a plate-shaped body.

  In addition, it is possible to appropriately replace the constituent elements in the above-described embodiments with well-known constituent elements without departing from the gist of the present invention, and the above-described modified examples may be appropriately combined.

  The surface to be inspected of the object can be inspected over a predetermined range while suppressing the apparatus from becoming large.

DESCRIPTION OF SYMBOLS 1 Inspection apparatus 11 Light source 12 Half mirror 13 Imaging means 14 Processing part 15 Driving means L Light beam W Target object

Claims (4)

A light source that emits light rays;
A half mirror that reflects the light from the light source and irradiates the surface to be inspected of the object;
An imaging means disposed on the opposite side of the object sandwiching the half mirror, and imaging the surface to be inspected of the object irradiated with light from the light source via the half mirror;
A processing unit that inspects an object based on imaging data from the imaging means,
The light source emits an annular light beam that gradually increases in diameter as it moves away from the light source along the optical axis direction;
Drive means for supporting the light source so as to be able to contact and separate along the optical axis direction with respect to the half mirror ,
By inspecting the surface to be inspected while moving the light irradiation position on the surface to be inspected by moving the light source in the optical axis direction by the driving means and changing the diameter of the light ray on the surface to be inspected. inspection apparatus according to claim to Rukoto.   The inspection apparatus according to claim 1, wherein a circular light-shielding mask is arranged on the entire emission surface of the light source that emits light rays except for the outer peripheral edge. An inspection method for inspecting an object based on imaging data of an inspected surface of the object irradiated with light,
Inspecting an object using the inspection device according to claim 1 or 2 ,
2. The inspection method according to claim 1, wherein the surface to be inspected of the object is a peripheral surface that extends around the optical axis of the light beam that is reflected by the half mirror and travels toward the object.   The processing unit inspects the presence or absence of scratches on the surface to be inspected based on imaging data from the imaging means,
  The line width of the light beam is less than or equal to the size of the scratch that needs to be detected,
  The inspection method according to claim 3, wherein the object is a conical body, and an outer peripheral surface thereof is the surface to be inspected.

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